|Year|Competition|Venue|Position|Notes|
|---|---|---|---|---|
|1991|World Race Walking Cup|San Jose, United States|12th|50 km|
|1991|World Championships|Tokyo, Japan|13th|50 km|
|1992|Olympic Games|Barcelona, Spain|18th|50 km|
|1993|World Championships|Stuttgart, Germany|7th|50 km|
|1994|Asian Games|Hiroshima, Japan|3rd|50 km|
|1995|World Championships|Gothenburg, Sweden|20th|50 km|
|1997|World Championships|Athens, Greece|6th|50 km|
|1998|Asian Games|Bangkok, Thailand|2nd|50 km|
|1999|World Championships|Seville, Spain|15th|50 km|
|2000|Olympic Games|Sydney, Australia|36th|50 km|
|2001|World Championships|Edmonton, Canada|29th|50 km|
|2003|World Championships|Paris, France|DSQ|50 km|

Question: how many world championships did imamura participate in?
Answer: 7